1. Field of the Invention
The present invention relates to a pan-releasing type oil composition. The invention relates more particularly to a oil composition which is excellent in the function of preventing food materials from sticking to a cooking tool, a dry sand mold, a roof plate, etc. at the time of food heat-cooking, and is free from the browning and coloring of phospholipids due to heating or the emission of a bad smell caused by the thermal decomposition and denaturation of the phospholipids.
2. Description of the Prior Art
At the time of manufacture of cakes and breads or heat-cooking of roasts and fries, fats and oils are used for the purpose of preventing food materials from sticking to a cooking tool, a dry sand mold, a roof plate, etc. after heat-baking. Heretofore, it is known that among various surface active substances, only lecithin is specifically effective for the separation of food materials which tend to give rise to the sticking by heating, such as sponge cake dough and eggroll stuff. Fats and oils in which soybean lecithin is added to and dissolved in vegetable oils have been used as pan-releasing oils.
In such a case, the lecithin is a phospholipid mixture having phosphatidyl choline, phosphatidyl ethanolamine, etc. for its main ingredients. The representative is lecithin obtained by extraction or purification from soybeans or egg yolk.
Natural lecithins such as the soybean lecithin, yolk lecithin, etc. are very unstable substances; they present browing phenomena and are colored dark brown when heated to temperatures above 150.degree. C. even if they are in a state where they are protected by fats and oils. Further, they suffer the disadvantage that they emit bad smells or offensive smells arising from decomposition products and denaturation products of lecithin. Accordingly, their application methods and amounts of them used are considerably restricted.
With the object of reforming lecithin, hydroxylated lecithin is used as a pan-releasing type oil (U.S. Pat. No. 3,661,605), and lecithin with HLB in a specific range is used (U.S. Pat. No. 3,896,975). All of these prior arts, however, do not aim at the improvement of the above-described disadvantages (coloring and emission of bad smells or offensive smells) of lecithin.
Meanwhile, for the purpose of preventing lecithin from browning by heating, succinic acid or sodium succinate is mixed (Published Examined Japanese Patent Application No. 48520/86), acidic amino acid and basic amino acid are mixed (Published Unexamined Japanese Patent Application No. 126206/79), or sodium glutamate is mixed (Published Unexamined Japanese Patent Application No. 127408/79). However, these prior arts do not lead to the substantial obviation of the aforesaid disadvantages.